On the hull number of some graph classes

J Araujo, V Campos, F Giroire, N Nisse… - Theoretical Computer …, 2013 - Elsevier
In this paper, we study the geodetic convexity of graphs, focusing on the problem of the
complexity of computing a minimum hull set of a graph in several graph classes. For any two …

[HTML][HTML] Inapproximability results for graph convexity parameters

EMM Coelho, MC Dourado, RM Sampaio - Theoretical Computer Science, 2015 - Elsevier
In this paper, we prove several inapproximability results on the P 3-convexity and the
geodesic convexity in graphs. We prove that determining the P 3-hull number and the …

[HTML][HTML] On the Carathéodory number of interval and graph convexities

MC Dourado, D Rautenbach, VF Dos Santos… - Theoretical Computer …, 2013 - Elsevier
Inspired by a result of Carathéodory [Über den Variabilitätsbereich der Fourierschen
Konstanten von positiven harmonischen Funktionen, Rend. Circ. Mat. Palermo 32 (1911) …

The convexity of induced paths of order three

RT Araújo, RM Sampaio, JL Szwarcfiter - Electronic Notes in Discrete …, 2013 - Elsevier
In this paper, we introduce a new convexity on graphs similar to the well known P 3-
convexity [R. Barbosa, E. Coelho, M. Dourado, D. Rautenbach, JL Szwarcfiter, A. Toman. On …

[HTML][HTML] On the P3-hull number of some products of graphs

EMM Coelho, H Coelho, JR Nascimento… - Discrete Applied …, 2019 - Elsevier
Let G be a finite, simple, and undirected graph and let S be a set of vertices of G. If every
vertex having two neighbors inside S is also in S, then S is P 3-convex. The P 3-convex hull …

Polynomial time algorithms for computing a minimum hull set in distance-hereditary and chordal graphs

MM Kanté, L Nourine - SIAM Journal on Discrete Mathematics, 2016 - SIAM
We give linear and polynomial time algorithms for computing the hull number of distance-
hereditary and chordal graphs, respectively. The complexity of computing the hull number in …

Polynomial time algorithms for computing a minimum hull set in distance-hereditary and chordal graphs

MM Kanté, L Nourine - International Conference on Current Trends in …, 2013 - Springer
We give linear and polynomial time algorithms for computing a minimum hull-set in distance-
hereditary and chordal graphs respectively. Prior to our result a polynomial time algorithm …

[HTML][HTML] Hull number: P5-free graphs and reduction rules

J Araújo, G Morel, L Sampaio, R Soares… - Discrete Applied …, 2016 - Elsevier
In this paper, we study the (geodesic) hull number of graphs. For any two vertices u, v∈ V of
a connected undirected graph G=(V, E), the closed interval I [u, v] of u and v is the set of …

Pursuit-evasion, decompositions and convexity on graphs

RP Soares - 2013 - theses.hal.science
This thesis focuses on the study of structural properties of graphs whose understanding
enables the design of efficient algorithms for solving optimization problems. We are …

Algorithmic aspects of graph colourings heuristics

L Sampaio - 2012 - theses.hal.science
A proper colouring of a graph is a function that assigns a colour to each vertex with the
restriction that adjacent vertices are assigned with distinct colours. Proper colourings are a …